26 STATE POMOLOGICAL SOCIETY. 



of 4 lbs. copper sulphate, 4 lbs. fresh lime and 40 gallons of 

 water. The copper sulphate should be dissolved in three or four 

 gallons of water in a wooden or earthen vessel and the lime 

 (which must be absolutely fresh) should be slaked in a separate 

 vessel, and diluted with water till it is of a milky nature. When 

 ready for use, the two solutions may be mixed in a third vessel,, 

 care being taken to stir constantly during the process. In every 

 case, the mixture should be passed through a sieve of number 

 50 brass wire cloth, or through cheese cloth backed by common 

 window screen wire. This straining is necessary to prevent 

 clogging of the nozzle. 



Potassium Sulphide. Potassium sulphide, or "liver of sul- 

 phur" is specially valuable as a preventive of gooseberry mildew 

 and for use in the greenhouse. In using this material four 

 ounces of the sulphide are dissolved in ten gallons of water. 



Paris Green. This material is the one which is always relia- 

 ble for the destruction of leaf-eating insects. Many other forms 

 of arsenic have been recommended, but none have proved so 

 generally satisfactory as Paris green.f It is practically insolu- 

 ble in water, but as there is usually present a small amount of 

 soluble arsenic, it is always well to add a little fresh lime to 

 the mixture before applying, that injury to the foliage may be 

 averted. Paris green is generally mixed with water in the pro- 

 portion of I pound to 200 gallons. If lime is added, however, 

 a pound to 100 gallons may be used. 



Kerosene. Kerosene is the specific for all sucking insects. 

 It kills by contact and, owing" to its cheapness and efficiency, will 

 probably remain the most valuable insecticide for this class of 

 insects. The form in which it is usually applied is the soap 

 emulsion, but there are now several forms of spray pumps which 

 make a mechanical mixture of kerosene and water, thus greatly 

 reducing the labor. 



Tobacco. A strong decoction of tobacco ("tobacco tea") is 

 often used with success in destroying the lice upon rose bushes 

 and tender, soft-wooded plants. 



t Among the cheaper substitutes for Paris green are "Green Arsenite," "Para- 

 grene," "Emerahl Green," "Arsenite of Soda," "Arsenate of I^ead," etc. With the 

 exception of the last named, which is largely nsed by the Gypsy Moth Commis- 

 sion of Massachusetts, the substitutes are still to be considered as experimental. 



